| 摘要 |
A viscous material dispenser (for liquid soap and the like) comprises a plunger with a roller connected to a flexible arm and a reservoir in fluid communication with a nozzle retained in a nozzle housing. Depressing the plunger pinches the nozzle closed between the roller and the nozzle housing and bends the flexible arm as the roller progresses along the length of the nozzle in the nozzle housing. Depressing the plunger also opens the nozzle exiting from the bottom of the reservoir. In one embodiment the reservoir is in fluid communication with an air chamber. Depressing the plunger increases the pressure in the air chamber and this pressurized air is conducted through a duct into the reservoir. The duct terminates in a portion which turns back on the remainder of the duct and this portion incorporates a one-way non-return valve so that pressure in the reservoir may be built up with consecutive strokes of the plunger due to the non-return valve. When air is pumped through the duct, a bubble of air is trapped between the valve and the mouth of the duct which prevents fouling of the valve by the viscous material. The reservoir may receive a sac of viscous material comprising a sac nozzle with a rigid extension with which the sac nozzle is threaded into and pulled through the nozzle in the nozzle housing. |
